Conventional concrete block construction uses rectangular blocks which are layered in courses and supported on a concrete foundation. Great care and skill is required to achieve level courses and to form truly vertical walls, resulting in high labor costs.
Numerous attempts have been made to provide a building block construction which may be assembled by unskilled labor. Such systems typically include a design which insures uniformity of construction as the blocks are assembled, such as mating protrusions and indentations, or holes which are formed in the blocks and aligned between adjacent blocks, such as by the use of pins or rods.
Although prior designs have experienced a certain degree of success, they have typically relied on the blocks as a structural component for carrying vertical loads in a structure formed by the blocks. The requirement to carry vertical loads has resulted in the blocks requiring additional material for withstanding the stresses of the loads, and thus have increased the costs of the blocks. In addition, materials such as plastic are known to flex and/or crack over time when exposed to stress, such that there is a need for a structural construction system incorporating blocks formed of plastics material, but which isolates stresses from the blocks while providing a reliably strong structure.